The invention relates to a method for monitoring adequate oil lubrication of an internal combustion engine, in particular that of a vehicle, by means of a sensor arranged in an oil line of a pressure circulation lubrication system and connected to an electronic evaluation system. The invention also relates to an internal combustion engine for carrying out this method.
Proper functioning of the pressure circulation lubrication system is of decisive importance to the service life of internal combustion engines. If the oil film on the cylinder walls breaks down, the engine overheats very rapidly and this rapidly leads to serious engine damage. Currently, adequate oil lubrication of internal combustion engines is monitored only indirectly by sensors which measure the pressure in the oil line. If the pressure falls due, for example, to failure of the oil pump or a leak in the oil circuit, the driver receives a warning signal. In addition, the oil level in the oil pan is often monitored by means of a sensor in order to ensure that there is always a sufficiently large supply of oil.
It has been found in practice, however, that an oil pressure drop can often only be detected when serious engine damage has already occurred due to inadequate lubrication. Monitoring the oil level in the oil pan does not ensure an adequate oil supply either. Owing to dynamic driving states, e.g. when driving round a relatively long bend, when driving on a slope or during acceleration, the oil level in the oil pan can shift to such an extent that the oil pump draws in air instead of oil and, as a result, lubrication temporarily ceases and inadequate lubrication occurs.
The problem underlying the invention is to develop a method for monitoring adequate oil lubrication of an internal combustion engine by means of which a warning can be given as early as possible if there is a risk of inadequate engine lubrication. The intention is furthermore to develop an internal combustion engine which operates in accordance with such a method.